---
name: pi-map
description: Generates and maintains hierarchical paired project-analysis artifacts (`.pi-map.index.md` + `.pi-map.md`) so Pi agents can navigate and orient in a codebase without reading every source file.
---

# pi-project-map

A Pi skill that creates and maintains one paired analysis artifact set per non-ignored directory:

- `.pi-map.index.md` — routing-first index
- `.pi-map.md` — orientation-first rich map

## What it does

- scans the project and emits one paired map/index set per directory
- extracts per-file purpose, dependencies, and concepts via an LLM
- extracts exact exports/imports via AST parsing where supported
- patches artifacts incrementally after source edits
- validates stale, missing, broken, or inconsistent paired artifacts
- retrieves relevant context on demand via deterministic metadata scoring
- injects lightweight project-map guidance into agent context according to a configurable mode ladder

## Operating model

### Tier 0 — protocol
Always read the root `.pi-map.index.md` and the `Project Map Protocol` first.

### Tier 1 — routing
Use indexes first to decide where to go next. Open the strongest-match `.pi-map.md` files for orientation.

### Tier 2 — source
Read actual source, tests, config, and docs before editing or asserting exact runtime behavior.

**Trust boundary:**

> **index routes, map orients, source decides**

## Agent instructions

When project-map artifacts exist in the repo:

1. start with the root `.pi-map.index.md` and the `Project Map Protocol`
2. use indexes first to route into the right directory
3. read the local `.pi-map.md` plus relevant source before editing
4. run `project_map_patch <file>` (tool) or `project-map patch <file>` (CLI) after each source edit
5. run `project_map_validate` (tool) or `project-map validate` (CLI) before freshness-sensitive architectural decisions or final handoff
6. if validation shows localized discrepancies, run `project_map_validate` with `fix=true` (tool) or `project-map validate --fix` (CLI)
7. only if discrepancies are widespread or structural, run `project_map_reinit` (tool) or `project-map reinit` (CLI)
8. for targeted exploration, use `project_map_context <query>` (tool) or `project-map context <query>` (CLI)
9. in `strict` mode, only bypass the protocol-path guard with an explicit marker: `[PI_MAP_BYPASS: <brief justification>]`

## Prompt injection modes

The Pi extension can inject project-map guidance automatically. Behavior is controlled by `promptInjectionMode` in `.pi-project-map.json`.

### Before init
If no `.pi-map.md` / `.pi-map.index.md` artifacts exist, the extension emits a lightweight visible hint to run `project_map_init`. No synthetic or fake map content is injected.

### After init
Once real artifacts exist, the runtime guarantees that the **root pair** is loaded first:

- root `.pi-map.index.md`
- root `.pi-map.md`

Additional directory pairs may be expanded while the configured context budget allows, in shallow-first order.

### Mode ladder

| Mode | Behavior |
|------|----------|
| `off` | No automatic injection. Use tools/CLI manually. |
| `advisory` | Startup/init hints are shown. Root pair is not auto-loaded; read it manually when needed. |
| `strong` (default) | Root pair is auto-loaded, expansion stays within budget, and reinjection runs on relevant turns. |
| `strict` | Same as `strong`, but sensitive edits or architectural claims are guarded unless the protocol path is present or a bypass marker is provided. |

The **protocol path** means the outgoing context contains the canonical injected root-pair block and the trust-boundary text.

### Context budget
Default budget: **15% of the active model context window**, capped at **100k tokens**. The smaller of the relative and absolute values wins. If the runtime cannot discover the context window, it uses the absolute cap.

## Retrieval usage

`project_map_context` (tool) and `project-map context` (CLI) are **on-demand retrieval**, separate from automatic injection.

They do not call the LLM. They score paired metadata against the query and return a compact markdown bundle with:

- relevant indexes
- relevant maps
- likely files
- relevant symbols when useful

Always read the suggested indexes first, then maps, then verify critical behavior from source.

## Configuration

Create `.pi-project-map.json` in the project root:

```json
{
  "promptInjectionMode": "strong",
  "contextBudgetPercent": 15,
  "contextBudgetMaxTokens": 100000,
  "tagCap": 8,
  "workflowHintCap": 5,
  "llmProvider": "openai",
  "llmModel": "gpt-4o-mini",
  "reinitFullThresholdPercent": 10,
  "ignorePatterns": ["node_modules", ".git", "dist", "build"]
}
```

Providing `ignorePatterns` replaces the built-in default list, so include any defaults you want to keep.

- `reinitFullThresholdPercent` — when `project_map_reinit` targets a subtree that covers more than this percentage of project files, it falls back to full regeneration

Knobs that matter in practice:
- `promptInjectionMode` — `off` | `advisory` | `strong` | `strict`
- `contextBudgetPercent` / `contextBudgetMaxTokens` — caps automatic map/index injection
- `tagCap` / `workflowHintCap` — caps routing metadata per directory
- `llmProvider` / `llmModel` / `llmBaseUrl` — standalone CLI only
- `ignorePatterns` — discovery exclusions

## Tools and commands

| Tool (Pi) | CLI command | Purpose |
|-----------|-------------|---------|
| `project_map_init` | `project-map init [path]` | Generate all paired artifacts. |
| `project_map_patch` | `project-map patch <file>` | Regenerate the pair for the changed file's directory and refresh ancestors. |
| `project_map_validate` | `project-map validate [--fix]` | Check paired artifacts for staleness and discrepancies; optionally repair. |
| `project_map_reinit` | `project-map reinit [path]` | Smart regeneration: recomputes the target subtree plus ancestors, and only falls back to full regeneration when the subtree covers more than `reinitFullThresholdPercent` of project files (default 10%). |
| `project_map_context` | `project-map context <query>` | Retrieve a ranked context bundle for a natural-language query. |